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Objective: Overweight and obesity are characterized by excess adiposity and systemic, chronic, low-grade inflammation, which is associated with several metabolic disorders. The aim of this study was to assess the feasibility and tolerability of β-alanine supplementation and to explore the effects on cardiometabolic health and cardiovascular, hepatic, and renal function in adults with overweight and obesity., Methods: A total of 27 adults (44% female; mean [SD], age: 58 [10] years, BMI: 31.1 [2.9] kg/m 2 , hemoglobin A1c: 39.8 [4.3] mmol/mol) received β-alanine (4.8 g/day) or a matched placebo for 3 months. Feasibility and tolerability outcomes included adherence, side effects, recruitment, attrition, and blinding, and exploratory outcomes included biochemical markers, blood pressures, and transthoracic echocardiography parameters. Data were analyzed using a Bayesian approach presented with 95% credible intervals (CrI)., Results: β-alanine was well tolerated and adhered to (adherence: placebo, 0.91 [95% CrI: 0.84-0.95]; β-alanine, 0.92 [95% CrI: 0.85-0.95]), and side effects remained at or below baseline throughout. The probability that β-alanine supplementation affected cardiometabolic, cardiovascular, or clinical biochemical outcomes was low., Conclusions: Sustained-release β-alanine supplementation is well tolerated and adhered to in adults with overweight and obesity. Future research should consider more advanced metabolic conditions, which may benefit from longer duration supplementation., (© 2025 The Author(s). Obesity published by Wiley Periodicals LLC on behalf of The Obesity Society.)

This study compared the effects of 90° versus 40° hip flexion in the leg extension exercise on quadriceps femoris muscle hypertrophy. Twenty-two untrained men completed a ten-week intervention comprising two resistance training sessions per week. A within-participant design was used, with the lower limb side randomly allocated to the 40 or 90° condition. Muscle thickness of distal and proximal rectus femoris and vastus lateralis was quantified via ultrasound. Data were analysed within a Bayesian framework including univariate and multivariate mixed effect models with random effects to account for the within participant design. Differences between conditions were estimated as average treatment effects (ATE) and inferences were made based on posterior distributions and Bayes Factors (BF). Results indicated a greater hypertrophic response in the rectus femoris for the 40° condition, with "extreme" evidence supporting a hypertrophic response favouring the 40° hip angle for the rectus femoris (BF > 100; p(Distal/ATE & Proximal/ATE >0) > 0.999), and "strong" evidence supporting no difference in hypertrophic response for the vastus lateralis (BF = 0.07). Therefore, both conditions could be viable options for increasing quadriceps femoris hypertrophy. However, when training for maximizing rectus femoris hypertrophy among untrained men, we suggest training with a reduced hip flexion in the leg extension exercise.

Background: Although numerous attempts to demonstrate inter-individual differences in trainability across various outcomes have been unsuccessful, the investigation of maximal oxygen consumption (VO 2max ) trainability warrants further study., Objective: Our objective was to conduct the first systematic review and meta-analysis to evaluate inter-individual differences in VO 2max trainability across aerobic exercise training protocols utilizing non-exercising comparator groups., Methods: We conducted a literature search across three databases: EMBASE, PubMed and SCOPUS. The search strategy incorporated two main concepts: aerobic exercise training and VO 2max . Studies were included if they used human participants, employed standardized and supervised exercise training, reported absolute or relative VO 2max , included a non-exercise comparator group, reported VO 2max change scores for non-exercise and exercise groups and provided the standard deviation (SD) of change for all groups. We calculated the SD of individual response (SD IR ) to estimate the presence of inter-individual differences in trainability across all studies., Results: The literature search generated 32,968 studies, 24 of which were included in the final analysis. Our findings indicated that (1) the majority of variation in observed change scores following an intervention is due to measurement error, (2) calculating SD IR within a single study would not yield sufficient accuracy of SD IR due to generally small sample sizes and (3) meta-analysis of SD IR 2 across studies does not provide strong evidence for a positive value., Conclusion: Overall, our meta-analysis demonstrated that there is not strong evidence supporting the existence of VO 2max trainability across single interventions. As such, it appears unlikely that clinically relevant predictors of VO 2max response will be discovered. Registration can be found online ( https://doi.org/10.17605/OSF.IO/X9VU3 )., Competing Interests: Declarations. Authors’ Contributions: Briefly, JR, NP, ZW, AK, JN, ML, KB, NS and BJG conducted the literature review, screening process and data extraction. JR, NP, PS and BJG contributed to the study conception and design and the writing of the first draft and commented on previous versions of the manuscript. All authors have read and approved the final version of the manuscript and agree with the order of presentation of the authors. Funding: This study was supported by funding provided to BJG from the Natural Sciences and Engineering Research Council of Canada (NSERC; Grant no. 402635). Competing Interests: The authors declare there are no competing interests. Data Availability: Data generated or analyzed during this study are available from the corresponding author upon reasonable request. Registration of this project can be found on the Open Science Framework ( https://doi.org/ https://doi.org/10.17605/OSF.IO/X9VU3 )., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: It is unknown whether there are differences in maximal oxygen uptake ( V O 2max ) response when prescribing intensity relative to traditional (TRAD) anchors or to physiological thresholds (THR)., Objectives: The present meta-analysis sought to compare: (a) mean change in V O 2max , (b) proportion of individuals increasing V O 2max beyond a minimum important difference (MID) and (c) response variability in V O 2max between TRAD and THR., Methods: Electronic databases were searched, yielding data for 1544 individuals from 42 studies. Two datasets were created, comprising studies with a control group ('controlled' studies), and without a control group ('non-controlled' studies). A Bayesian approach with multi-level distributional models was used to separately analyse V O 2max change scores from the two datasets and inferences were made using Bayes factors (BF). The MID was predefined as one metabolic equivalent (MET; 3.5 mL kg -1  min -1 )., Results: In controlled studies, mean V O 2max change was greater in the THR group compared with TRAD (4.1 versus 1.8 mL kg -1  min -1 , BF > 100), with 64% of individuals in the THR group experiencing an increase in V O 2max  > MID, compared with 16% of individuals taking part in TRAD. Evidence indicated no difference in standard deviation of change between THR and TRAD (1.5 versus 1.7 mL kg -1  min -1 , BF = 0.55), and greater variation in exercise groups relative to non-exercising controls (1.9 versus 1.3 mL kg -1  min -1 , BF = 12.4). In non-controlled studies, mean V O 2max change was greater in the THR group versus the TRAD group (4.4 versus 3.4 mL kg -1  min -1 , BF = 35.1), with no difference in standard deviation of change (3.0 versus 3.2 mL kg -1  min -1 , BF = 0.41)., Conclusion: Prescribing exercise intensity using THR approaches elicited superior mean changes in V O 2max and increased the likelihood of increasing V O 2max beyond the MID compared with TRAD. Researchers designing future exercise training studies should thus consider the use of THR approaches to prescribe exercise intensity where possible. Analysis comparing interventions with controls suggested the existence of intervention response heterogeneity; however, evidence was not obtained for a difference in response variability between THR and TRAD. Future primary research should be conducted with adequate power to investigate the scope of inter-individual differences in V O 2max trainability, and if meaningful, the causative factors., Competing Interests: Declarations Funding No funding and financial assistance was used for this review. Conflicts of Interest Authors Samuel J. R. Meyler, Paul A. Swinton, Lindsay Bottoms, Lance C. Dalleck, Ben Hunter, Mark A. Sarzynski, David Wellsted, Camilla J. Williams and Daniel Muniz-Pumares declare that they have no conflicts of interest relevant to the content of this review. Availability of Data and Material Datasets analysed in the current review are available upon reasonable request but are subject to permission from original authors. Ethics Approval Each study received ethical approval from their respective institutions, conformed to the guidelines of the Declaration of Helsinki and obtained written informed consent from each participant prior to commencing data collection. Author Contributions All authors: (1) made substantial contributions to the conception or design of the work or to the acquisition, analysis, or interpretation of data and (2) drafted the work or revised it critically for important intellectual content. All authors read and approved the final version of the manuscript., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Background: Although nutrition and exercise both influence bone metabolism, little is currently known about their interaction, or whether nutritional intervention can modulate the bone biomarker response to acute exercise. Improved understanding of the relationships between nutrition, exercise and bone metabolism may have substantial potential to inform nutritional interventions to protect the bone health of exercising individuals, and to elucidate mechanisms by which exercise and nutrition influence bone., Objective: The aim was to synthesise available evidence related to the influence of nutrition on the response of the bone biomarkers procollagen type 1 N-terminal propeptide (P1NP) and C-terminal telopeptide of type 1 collagen (CTX-1) to acute exercise, using a systematic review and meta-analytic approach., Methods: Studies evaluating the influence of nutritional status or intervention on the bone biomarker response to an acute exercise bout were included and separated into four categories: (1) feeding status and energy availability, (2) macronutrients, (3) micronutrients and (4) other. Studies conducted on healthy human populations of any age or training status were included. Meta-analysis was conducted when data from at least five studies with independent datasets were available. In the case of insufficient data to warrant meta-analysis, results from individual studies were narratively synthesised and standardised mean effect sizes visually represented., Results: Twenty-two articles were included. Of these, three investigated feeding status or energy availability, eight macronutrients, eight micronutrients (all calcium) and six other interventions including dairy products or collagen supplementation. Three studies had more than one intervention and were included in all relevant outcomes. The largest and most commonly reported effects were for the bone resorption marker CTX-1. Meta-analysis indicated that calcium intake, whether provided via supplements, diet or infusion, reduced exercise-induced increases in CTX-1 (effect size - 1.1; 95% credible interval [CrI] -  2.2 to - 0.05), with substantially larger effects observed in studies that delivered calcium via direct infusion versus in supplements or foods. Narrative synthesis suggests that carbohydrate supplementation may support bone during acute exercise, via reducing exercise-induced increases in CTX-1. Conversely, a low-carbohydrate/high-fat diet appears to induce the opposite effect, as evidenced by an increased exercise associated CTX-1 response, and reduced P1NP response. Low energy availability may amplify the CTX-1 response to exercise, but it is unclear whether this is directly attributable to energy availability or to the lack of specific nutrients, such as carbohydrate., Conclusion: Nutritional intervention can modulate the acute bone biomarker response to exercise, which primarily manifests as an increase in bone resorption. Ensuring adequate attention to nutritional factors may be important to protect bone health of exercising individuals, with energy, carbohydrate and calcium availability particularly important to consider. Although a wide breadth of data were available for this evidence synthesis, there was substantial heterogeneity in relation to design and intervention characteristics. Direct and indirect replication is required to confirm key findings and to generate better estimates of true effect sizes., Competing Interests: Declarations Conflict of interest None of the authors have any conflict of interest to declare. Funding ED, GPE and LP are financially supported by the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP 2019/05616-6; 2019/26899-6; 2020/07860-9 and 2022/09028-4). No other funding sources were used to assist in the preparation of this article. Data availability The data that support the findings of this study are available within the paper, associated online resources or within the original articles cited herein. Author contributions ED conceived the original idea for this article, and the protocol was developed by ED, PAS, CS and GK. ED conducted the searches and GPE, AD and KK selected the studies. Data were extracted by GPE and AD, and GPE, AD, LP and LT evaluated the risk of bias of each study. PAS conducted all statistical analyses, and results were interpreted by ED, CS, GK, BG and LB. ED wrote the initial manuscript draft, which was then edited in accordance with ongoing critical input from all authors. All authors read and approved the final manuscript., (© 2024. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

We systematically searched the literature for studies with a randomized design that compared different inter-set rest interval durations for estimates of pre-/post-study changes in lean/muscle mass in healthy adults while controlling all other training variables. Bayesian meta-analyses on non-controlled effect sizes using hierarchical models of all 19 measurements (thigh: 10; arm: 6; whole body: 3) from 9 studies meeting inclusion criteria analyses showed substantial overlap of standardized mean differences across the different inter-set rest periods [binary: short: 0.48 (95%CrI: 0.19-0.81), longer: 0.56 (95%CrI: 0.24-0.86); Four categories: short: 0.47 (95%CrI: 0.19-0.80), intermediate: 0.65 (95%CrI: 0.18-1.1), long: 0.55 (95%CrI: 0.15-0.90), very long: 0.50 (95%CrI: 0.14-0.89)], with substantial heterogeneity in results. Univariate and multivariate pairwise meta-analyses of controlled binary (short vs. longer) effect sizes showed similar results for the arm and thigh with central estimates tending to favor longer rest periods [arm: 0.13 (95%CrI: -0.27 to 0.51); thigh: 0.17 (95%CrI: -0.13 to 0.43)]. In contrast, central estimates closer to zero but marginally favoring shorter rest periods were estimated for the whole body [whole body: -0.08 (95%CrI: -0.45 to 0.29)]. Subanalysis of set end-point data indicated that training to failure or stopping short of failure did not meaningfully influence the interaction between rest interval duration and muscle hypertrophy. In conclusion, results suggest a small hypertrophic benefit to employing inter-set rest interval durations >60 s, perhaps mediated by reductions in volume load. However, our analysis did not detect appreciable differences in hypertrophy when resting >90 s between sets, consistent with evidence that detrimental effects on volume load tend to plateau beyond this time-frame. Systematic Review Registration: OSF, https://doi.org/10.17605/OSF.IO/YWEVC., Competing Interests: BJS formerly served on the scientific advisory board for Tonal Corporation, a manufacturer of fitness equipment. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest. The author(s) declared that they were an editorial board member of Frontiers, at the time of submission. This had no impact on the peer review process and the final decision., (© 2024 Singer, Wolf, Generoso, Arias, Delcastillo, Echevarria, Martinez, Androulakis Korakakis, Refalo, Swinton and Schoenfeld.)

Background: Resistance exercise is the most common training modality included within strength and conditioning (S&C) practice. Understanding dose-response relationships between resistance training and a range of outcomes relevant to physical and sporting performance is of primary importance for quality S&C prescription., Objectives: The aim of this meta-analysis was to use contemporary modelling techniques to investigate resistance-only and resistance-dominant training interventions, and explore relationships between training variables (frequency, volume, intensity), participant characteristics (training status, sex), and improvements across a range of outcome domains including maximum strength, power, vertical jump, change of direction, and sprinting performance., Methods: Data were obtained from a database of training studies conducted between 1962 and 2018, which comprised healthy trained or untrained adults engaged in resistance-only or resistance-dominant interventions. Studies were not required to include a control group. Standardized mean difference effect sizes were calculated and interventions categorized according to a range of training variables describing frequency (number of sessions per week), volume (number of sets and repetitions performed), overall intensity (intensity of effort and load, categorised as low, medium or high), and intensity of load (represented as % of one-repetition maximum [1RM] prescribed). Contemporary modelling techniques including Bayesian mixed-effects meta-analytic models were fitted to investigate linear and non-linear dose-responses with models compared based on predictive accuracy., Results: Data from a total of 295 studies comprising 535 groups and 6,710 participants were included with analyses conducted on time points ≤ 26 weeks. The best performing model included: duration from baseline, average number of sets, and the main and interaction effects between outcome domain and intensity of load (% 1RM) expressed non-linearly. Model performance was not improved by the inclusion of participant training status or sex., Conclusions: The current meta-analysis represents the most comprehensive investigation of dose-response relationships across a range of outcome domains commonly targeted within strength and conditioning to date. Results demonstrate the magnitude of improvements is predominantly influenced by training intensity of load and the outcome measured. When considering the effects of intensity as a % 1RM, profiles differ across outcome domains with maximum strength likely to be maximised with the heaviest loads, vertical jump performance likely to be maximised with relatively light loads (~ 30% 1RM), and power likely to be maximised with low to moderate loads (40-70% 1RM)., (© 2024. The Author(s).)

The idiom 'more high-quality research is needed ' has become the slogan for sport and exercise physiology-based research in female athletes. However, in most instances, it is challenging to address this gap of high-quality research in elite female athletes at a single study site due to challenges in recruiting enough participants with numerous menstrual cycle and contraceptive pill permutations. Accordingly, we have assembled an international multisite team to undertake an innovative project for female athletes, which investigates the effects of changes in endogenous and exogenous oestrogen and progesterone/progestins across the menstrual cycle and in response to second-generation combined monophasic contraceptive pill use, on aspects of exercise physiology and athletic performance. This project will employ the current gold-standard methodologies in this area, resulting in an adequately powered dataset. This protocol paper describes the consortium-based approach we will undertake during this study., Competing Interests: Competing interests: KJE-S has received funding/honoraria from Arsenal Football Club, The UK Sports Institute, the European Club Association, Gatorade Sport Science Institute, Hologic, Science in Sport, and the UK Ministry of Defence to support female athletes. None of these funds have direct competing interests with the Feminae project. TRF has no competing or conflicts of interest. SMA has received funding from the US Department of Defence, United States Marine Corps, the Board of Medicine, and various industry sources to support research on athletic females. None of these funds have direct competing interests with the Feminae project. ED is supported by a research grant from the Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP: 2019/05616-6 and 2019/26899-6) for a project unrelated to this one. She has no competing interests or conflicts to declare. BS is supported by a research grant from the São Paulo Research Foundation (Fundação de Amparo à Pesquisa do Estado de São Paulo, FAPESP: 2021/06836-0) for a project unrelated to this one. None of these funds have direct competing interests with the Feminae project. MH has no competing or conflicts of interest. JI has no competing or conflicts of interest. RM has no competing or conflicts of interest. CM has received funding from the Australian Institute of Sport, the Queensland Academy of Sport, and an industry partner (cannot be named here) to conduct research on female athletes. None of these grants have direct competing interests with the Feminae project. JST is a Canada Research Chair funded by the Canadian Institutes of Health Research. This funding does not have a direct competing interest with the Feminae project. KEA has received funding/honoraria from the Wu Tsai Human Performance Alliance, Gatorade Sport Science Institute, Hologic, UptoDate, and the United States Olympic and Paralympic Committee. This funding does not have a direct competing interest with the Feminae project. CML has no competing or conflicts of interest. CS has received funding from the UK Ministry of Defence to conduct research on female military personnel. This funding does not have direct competing interests with the Feminae project. TS has received funding/honoraria from the Wu Tsai Human Performance Alliance, Ineos, Science in Sport (Sis) Own The Podium, Gatorade Sport Science Institute and Lululemon Athletica to support research, including projects on female participants. None of these grants have a direct competing interest with the Feminae project. PS has no competing or conflicts of interest. ACH has no competing or conflicts of interest., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Sufficient high-quality studies in sport science using women as participants are lacking, meaning that our knowledge and understanding of female athletes in relation to their ovarian hormone profiles is limited. Consortia can be used to pool talent, expertise and data, thus accelerating our learning on a given topic and reducing research waste through collaboration. To this end, we have assembled an international multisite team, described here, to investigate the effects of the menstrual cycle and contraceptive pill phase on aspects of exercise physiology and sports performance in female athletes. We intend to produce an adequately powered, high-quality dataset, which can be used to inform the practices of female athletes. Our approach will also employ research transparency-through the inclusion of a process evaluation-and reproducibility-through a standardised study protocol., Competing Interests: Competing interests: KES has received funding from Arsenal Football Club, The English Institute of Sport, the European Club Association and the UK Ministry of Defence to conduct research on female athletes. None of these grants have direct competing interests with the Feminae project. KA has received funding/honoraria from the Wu Tsai Human Performance Alliance, Gatorade Sport Science Institute, Hologic, UptoDate and the US Olympic and Paralympic Committee. This funding does not have a direct competing interest with the Feminae project. CML has no competing or conflicts of interest. CM has received funding from the Australian Institute of Sport, the Queensland Academy of Sport, and an industry partner (cannot be named here) to conduct research on female athletes. None of these grants have direct competing interests with the Feminae project. CS has received funding from the UK Ministry of Defence to conduct research on female military personnel. This funding does not have direct competing interests with the Feminae project. TS has received funding/honoraria from the Wu Tsai Human Performance Alliance, Ineos, Science in Sport (Sis) Own The Podium, Gatorade Sport Science Institute and Lululemon Athletica to support research, including projects on female participants. None of these grants have a direct competing interest with the Feminae project. PAS has no competing or conflicts of interest. ACH has no competing or conflicts of interest., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Background: Tendinopathy is a common, painful and functionally limiting condition, primarily managed conservatively using exercise therapy., Review Questions: (i) What exercise interventions have been reported in the literature for which tendinopathies? (ii) What outcomes have been reported in studies investigating exercise interventions for tendinopathy? (iii) Which exercise interventions are most effective across all tendinopathies? (iv) Does type/location of tendinopathy or other specific covariates affect which are the most effective exercise therapies? (v) How feasible and acceptable are exercise interventions for tendinopathies?, Methods: A scoping review mapped exercise interventions for tendinopathies and outcomes reported to date (questions i and ii). Thereafter, two contingent systematic review workstreams were conducted. The first investigated a large number of studies and was split into three efficacy reviews that quantified and compared efficacy across different interventions (question iii), and investigated the influence of a range of potential moderators (question iv). The second was a convergent segregated mixed-method review (question v). Searches for studies published from 1998 were conducted in library databases ( n = 9), trial registries ( n = 6), grey literature databases ( n = 5) and Google Scholar. Scoping review searches were completed on 28 April 2020 with efficacy and mixed-method search updates conducted on 19 January 2021 and 29 March 2021., Results: Scoping review - 555 included studies identified a range of exercise interventions and outcomes across a range of tendinopathies, most commonly Achilles, patellar, lateral elbow and rotator cuff-related shoulder pain. Strengthening exercise was most common, with flexibility exercise used primarily in the upper limb. Disability was the most common outcome measured in Achilles, patellar and rotator cuff-related shoulder pain; physical function capacity was most common in lateral elbow tendinopathy. Efficacy reviews - 204 studies provided evidence that exercise therapy is safe and beneficial, and that patients are generally satisfied with treatment outcome and perceive the improvement to be substantial. In the context of generally low and very low-quality evidence, results identified that: (1) the shoulder may benefit more from flexibility (effect size Resistance:Flexibility = 0.18 [95% CrI 0.07 to 0.29]) and proprioception (effect size Resistance:Proprioception = 0.16 [95% CrI -1.8 to 0.32]); (2) when performing strengthening exercise it may be most beneficial to combine concentric and eccentric modes (effect size EccentricOnly:Concentric+Eccentric = 0.48 [95% CrI -0.13 to 1.1]; and (3) exercise may be most beneficial when combined with another conservative modality (e.g. injection or electro-therapy increasing effect size by ≈0.1 to 0.3). Mixed-method review - 94 studies (11 qualitative) provided evidence that exercise interventions for tendinopathy can largely be considered feasible and acceptable, and that several important factors should be considered when prescribing exercise for tendinopathy, including an awareness of potential barriers to and facilitators of engaging with exercise, patients' and providers' prior experience and beliefs, and the importance of patient education, self-management and the patient-healthcare professional relationship., Limitations: Despite a large body of literature on exercise for tendinopathy, there are methodological and reporting limitations that influenced the recommendations that could be made., Conclusion: The findings provide some support for the use of exercise combined with another conservative modality; flexibility and proprioception exercise for the shoulder; and a combination of eccentric and concentric strengthening exercise across tendinopathies. However, the findings must be interpreted within the context of the quality of the available evidence., Future Work: There is an urgent need for high-quality efficacy, effectiveness, cost-effectiveness and qualitative research that is adequately reported, using common terminology, definitions and outcomes., Study Registration: This project is registered as DOI: 10.11124/JBIES-20-00175 (scoping review); PROSPERO CRD 42020168187 (efficacy reviews); https://osf.io/preprints/sportrxiv/y7sk6/ (efficacy review 1); https://osf.io/preprints/sportrxiv/eyxgk/ (efficacy review 2); https://osf.io/preprints/sportrxiv/mx5pv/ (efficacy review 3); PROSPERO CRD42020164641 (mixed-method review)., Funding: This project was funded by the National Institute for Health and Care Research (NIHR) HTA programme and will be published in full in HTA Journal; Vol. 27, No. 24. See the NIHR Journals Library website for further project information.

Purpose: The objective of this study is to investigate whether heterogeneous treatment effects occur for changes in inspiratory muscle strength, perceived dyspnea, and health-related quality of life after 8 wk of unsupervised home-based inspiratory muscle training (IMT) in adults with postacute coronavirus disease 2019 (COVID-19) syndrome., Methods: In total, 147 adults with self-reported prior COVID-19 either completed an 8-wk home-based IMT intervention ( n = 111, 92 females, 48 ± 11 yr, 9.3 ± 3.6 months postacute COVID-19 infection) or acted as "usual care" wait list controls ( n = 36, 34 females, 49 ± 12 yr, 9.4 ± 3.2 months postacute COVID-19 infection)., Results: Applying a Bayesian framework, we found clear evidence of heterogeneity of treatment response for inspiratory muscle strength: the estimated difference between standard deviations (SD) of the IMT and control groups was 22.8 cm H 2 O (75% credible interval (CrI), 4.7-37.7) for changes in maximal inspiratory pressure (MIP) and 86.8 pressure time units (75% CrI, 55.7-116.7) for sustained MIP (SMIP). Conversely, there were minimal differences in the SD between the IMT and the control group for changes in perceived dyspnea and health-related quality of life, providing no evidence of heterogeneous treatment effects. Higher cumulative power during the IMT intervention was related to changes in MIP ( β = 10.9 cm H 2 O (95% CrI, 5.3-16.8) per 1 SD) and SMIP ( β = 63.7 (32.2-95.3) pressure time units per 1 SD), clearly indicating an IMT dose response for changes in inspiratory muscle strength. Older age (>50 yr), a longer time postacute COVID-19 (>3 months), and greater severity of dyspnea at baseline were also associated with smaller improvements in inspiratory muscle strength., Conclusions: Heterogeneous individual responses occurred after an 8-wk home-based IMT program in people with postacute COVID-19 syndrome. Consistent with standard exercise theory, larger improvements in inspiratory muscle strength are strongly related to a greater cumulative dose of IMT., (Copyright © 2023 by the American College of Sports Medicine.)

Objective: To investigate potential moderating effects of resistance exercise dose components including intensity, volume and frequency, for the management of common tendinopathies., Design: Systematic review with meta-analysis and meta-regressions., Data Sources: Including but not limited to: MEDLINE, CINAHL, SPORTDiscus, ClinicalTrials.gov and ISRCTN Registry., Eligibility Criteria for Selecting Studies: Randomised and non-randomised controlled trials investigating resistance exercise as the dominant treatment class, reporting sufficient information regarding ≥2 components of exercise dose., Results: A total of 110 studies were included in meta-analyses (148 treatment arms (TAs), 3953 participants), reporting on five tendinopathy locations (rotator cuff: 48 TAs; Achilles: 43 TAs; lateral elbow: 29 TAs; patellar: 24 TAs; gluteal: 4 TAs). Meta-regressions provided consistent evidence of greater pooled mean effect sizes for higher intensity therapies comprising additional external resistance compared with body mass only (large effect size domains: β BodyMass: External = 0.50 (95% credible interval (CrI): 0.15 to 0.84; p=0.998); small effect size domains ( β BodyMass: External = 0.04 (95% CrI: -0.21 to 0.31; p=0.619)) when combined across tendinopathy locations or analysed separately. Greater pooled mean effect sizes were also identified for the lowest frequency (less than daily) compared with mid (daily) and high frequencies (more than once per day) for both effect size domains when combined or analysed separately (p≥0.976). Evidence for associations between training volume and pooled mean effect sizes was minimal and inconsistent., Summary/conclusion: Resistance exercise dose is poorly reported within tendinopathy management literature. However, this large meta-analysis identified some consistent patterns indicating greater efficacy on average with therapies prescribing higher intensities (through inclusion of additional loads) and lower frequencies, potentially creating stronger stimuli and facilitating adequate recovery., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY. Published by BMJ.)

Background: Circulating biomarkers of bone formation and resorption are widely used in exercise metabolism research, but their responses to exercise are not clear. This study aimed to quantify group responses and inter-individual variability of P1NP and β-CTX-1 after prolonged, continuous running (60-120 min at 65-75% V̇O 2max ) in young healthy adult males using individual participant data (IPD) meta-analysis., Methods: The protocol was designed following PRISMA-IPD guidelines and was pre-registered on the Open Science Framework prior to implementation ( https://osf.io/y69nd ). Changes in P1NP and β-CTX-1 relative to baseline were measured during, immediately after, and in the hours and days following exercise. Typical hourly and daily variations were estimated from P1NP and β-CTX-1 changes relative to baseline in non-exercise (control) conditions. Group responses and inter-individual variability were quantified with estimates of the mean and standard deviation of the difference, and the proportion of participants exhibiting an increased response. Models were conducted within a Bayesian framework with random intercepts to account for systematic variation across studies., Results: P1NP levels increased during and immediately after running, when the proportion of response was close to 100% (75% CrI: 99 to 100%). P1NP levels returned to baseline levels within 1 h and over the next 4 days, showing comparable mean and standard deviation of the difference with typical hourly (0.1 ± 7.6 ng·mL -1 ) and daily (- 0.4 ± 5.7 ng·mL -1 ) variation values. β-CTX-1 levels decreased during and up to 4 h after running with distributions comparable to typical hourly variation (- 0.13 ± 0.11 ng·mL -1 ). There was no evidence of changes in β-CTX-1 levels during the 4 days after the running bout, when distributions were also similar between the running data and typical daily variation (- 0.03 ± 0.10 ng·mL -1 )., Conclusion: Transient increases in P1NP were likely biological artefacts (e.g., connective tissue leakage) and not reflective of bone formation. Comparable small decreases in β-CTX-1 identified in both control and running data, suggested that these changes were due to the markers' circadian rhythm and not the running intervention. Hence, prolonged continuous treadmill running did not elicit bone responses, as determined by P1NP and β-CTX-1, in this population., (© 2023. Springer Nature Switzerland AG.)

Background: Load-velocity relationships are commonly used to estimate one-repetition maximums (1RMs). Proponents suggest these estimates can be obtained at high frequencies and assist with manipulating loads according to session-by-session fluctuations. Given their increasing popularity and development of associated technologies, a range of load-velocity approaches have been investigated., Objective: This systematic review and individual participant data (IPD) meta-analysis sought to quantify the predictive validity of individualised load-velocity relationships for the purposes of 1RM prediction., Methods: In September 2022, a search of MEDLINE, SPORTDiscus, Web of Science and Scopus was conducted for published research, with Google Scholar, CORE and British Ethos also searched for unpublished research. Studies were eligible if they were written in English, and directly compared a measured and predicted 1RM using load-velocity relationships in the squat, bench press, deadlift, clean or snatch. IPD were obtained through requests to primary authors and through digitisation of in-text plots (e.g. Bland-Altman plots). Risk of bias was assessed using the Prediction model Risk Of Bias ASsessment Tool (PROBAST) and the review conducted in accordance with PRISMA-IPD guidelines and an a priori protocol. Absolute and scaled standard error of the estimates (SEE/SEE%) were calculated for two-stage aggregate analyses, with bootstrapping performed for sampling variances. Estimates were pooled using three-level hierarchical models with robust 95% confidence intervals (CIs). One-stage analyses were conducted with random intercepts to account for systematic differences across studies and prediction residuals calculated in the absolute scale (kg) and as a percentage of the measured 1RM. Moderator analyses were conducted by including a priori defined categorical variables as fixed effects., Results: One hundred and thirty-seven models from 26 studies were included with each identified as having low, unclear or high risk of bias. Twenty studies comprising 434 participants provided sufficient data for meta-analyses, with raw data obtained for 8 (32%) studies. Two-stage analyses identified moderate predictive validity [SEE% 9.8, 95% CI 7.4% to 12.2%, with moderator analyses demonstrating limited differences based on the number of loads (β 2Loads:>2Loads  = 0.006, 95% CI - 1.6 to 1.6%) or the use of individual or group data to determine 1RM velocity thresholds (β Group : Individualised  =  - 0.4, 95% CI - 1.9 to 1.0%)]. One-stage analyses identified that predictions tended to be overestimations (4.5, 95% CI 1.5 to 7.4 kg), which expressed as a percentage of measured 1RM was equal to 3.7 (95% CI 0.5 to 6.9% 1RM). Moderator analyses were consistent with those conducted for two-stage analyses., Conclusions: Load-velocity relationships tend to overestimate 1RMs irrespective of the modelling approach selected. On the basis of the findings from this review, practitioners should incorporate direct assessment of 1RM wherever possible. However, load-velocity relationships may still prove useful for general monitoring purposes (e.g. assessing trends across a training cycle), by providing high-frequency estimates of 1RM when direct assessment may not be logistically feasible. Given limited differences in predictions across popular load-velocity approaches, it is recommended that practitioners opting to incorporate this practice select the modelling approach that best suits their practical requirements., Registration: https://osf.io/agpfm/ ., (© 2023. The Author(s).)

Objective: To synthesise exercise therapy intervention data investigating patient rating outcomes for the management of tendinopathy., Design: A systematic review and meta-analysis of randomized controlled trials investigating exercise therapy interventions and reporting patient rating outcomes., Setting: Any setting in any country listed as very high on the human development index., Participants: People with a diagnosis of any tendinopathy of any severity or duration., Interventions: Exercise therapy for the management of tendinopathy comprising five different therapy classes: 1) resistance; 2) plyometric; 3) vibration; 4) flexibility, and 5) movement pattern retraining modalities, were considered for inclusion., Main Outcome Measures: Outcomes measuring patient rating of condition, including patient satisfaction and Global Rating of Change (GROC)., Results: From a total of 124 exercise therapy studies, 34 (Achilles: 41%, rotator cuff: 32%, patellar: 15%, elbow: 9% and gluteal: 3%) provided sufficient information to be meta-analysed. The data were obtained across 48 treatment arms and 1246 participants. The pooled estimate for proportion of satisfaction was 0.63 [95%CrI: 0.53-0.73], and the pooled estimate for percentage of maximum GROC was 53 [95%CrI: 38-69%]. The proportion of patients reporting positive satisfaction and perception of change increased with longer follow-up periods from treatment onset., Conclusion: Patient satisfaction and GROC appear similar and are ranked moderately high demonstrating that patients generally perceive exercise therapies positively. Further research including greater consistency in measurement tools is required to explore and where possible, identify patient- and exercise-related moderating factors that can be used to improve person-centred care., Systematic Review Registration Number: PROSPERO ID=CRD42020168187 CONTRIBUTION OF PAPER., Competing Interests: Conflicts of interest The authors declare no conflict of interest., (Copyright © 2023 The Authors. Published by Elsevier Ltd.. All rights reserved.)

Background: The purpose of this study was to investigate the reliability of spatio-temporal measurements applied within collective behaviour research in football., Methods: In silico experiments were conducted introducing positional errors (0.5, 2 and 4 m) representative of commercial tracking systems to match data from the 2020 European Championship qualifiers. Ratios of the natural variance ('signal') of spatio-temporal metrics obtained throughout sections of each game relative to the variance created by positional errors ('noise') were taken to calculate reliability. The effects of error magnitude and time of analysis (1, 5 and 15 mins; length of attack: <10, 10-20, >20 s) were assessed and compared using Cohen's f 2 effect size., Results: Error magnitude was found to exert greater influence on reliability (f 2  = 0.15 to 0.81) compared with both standard time of analysis (f 2  = 0.03 to 0.08) and length of attacks (f 2  = 0.15 to 0.32)., Discussion: The results demonstrate that technologies generating positional errors of 0.5 m or less should be expected to produce spatio-temporal metrics with high reliability. However, technologies that generate errors of 2 m or greater may produce unreliable values, particularly when analyses are conducted over discrete events such as attacks, which although critical, are often short in duration.

This large cohort study investigated reliability and validity of heel ultrasound to estimate bone mineral density in adults. Reliability calculated between left and right heels was relatively poor and so was criterion validity assessed relative to dual-energy X-ray absorptiometry. Heel ultrasound should be used cautiously when estimating bone mineral density., Introduction: Calcaneal quantitative ultrasound (QUS) may be used as a safe, low cost, and portable means to estimate bone mineral density (BMD) in large cohorts. The purpose of this study was to quantify the reliability and validity of QUS in comparison to dual-energy X-ray absorptiometry (DXA), which is the reference method for BMD measurement and diagnoses of osteopenia and osteoporosis., Methods: Bone outcomes measured on the large UK Biobank cohort were used. The reliability of QUS estimated BMD was quantified by comparing values obtained from the left and right heel measured in the same session. Criterion validity was assessed through agreement between QUS and DXA, quantifying correlations, and sensitivity and specificity of osteopenia and osteoporosis diagnoses., Results: Reliability calculations were made using data from over 216,000 participants demonstrating similar QUS BMD values between left and right heels in the absolute scale (Sd of difference for men: 0.12 and 0.07 g·cm -2 ). However, when expressed in relative scales, including concordance of quartiles, reliability was poor. Agreement between QUS and DXA was quantified using data from 5042 participants. Low to modest correlations (r = 0.29 to 0.44) were obtained between multiple QUS variables and DXA BMD, with sensitivity identified as very poor (0.05 to 0.23) for osteoporosis, and poor (0.37 to 0.62) for osteopenia diagnoses., Conclusions: The findings of this large comparative analysis identify that whilst calcaneal QUS has the potential to produce reliable absolute BMD measurements and demonstrate modest associations with DXA BMD measures, use of that information to make relative statements about participants in the context of the larger population or to appropriately diagnose osteopenia or osteoporosis may be severely limited., (© 2023. The Author(s).)

The purpose of this study was to compare the effects of electromagnetic resistance alone, as well as in combination with variable resistance or accentuated eccentric methods, with traditional dynamic constant external resistance exercise on myoelectric activity during elbow flexion. The study employed a within-participant randomized, cross-over design whereby 16 young, resistance-trained male and female volunteers performed elbow flexion exercise under each of the following conditions: using a dumbbell (DB); using a commercial electromagnetic resistance device (ELECTRO); variable resistance (VR) using a setting on the device that attempts to match the level of resistance to the human strength curve, and; eccentric overload (EO) using a setting on the device that increases the load by 50% on the eccentric portion of each repetition. Surface electromyography (sEMG) was obtained for the biceps brachii, brachioradialis and anterior deltoid on each of the conditions. Participants performed the conditions at their predetermined 10 repetition maximum. " The order of performance for the conditions was counterbalanced, with trials separated by a 10-min recovery period. The sEMG was synced to a motion capture system to assess sEMG amplitude at elbow joint angles of 30°, 50°, 70°, 90°, 110°, with amplitude normalized to the maximal activation. The anterior deltoid showed the largest differences in amplitude between conditions, where median estimates indicated greater concentric sEMG amplitude (~ 7-10%) with EO, ELECTRO and VR compared with DB. Concentric biceps brachii sEMG amplitude was similar between conditions. In contrast, results indicated a greater eccentric amplitude with DB compared to ELECTRO and VR, but unlikely to exceed a 5% difference. Data indicated a greater concentric and eccentric brachioradialis sEMG amplitude with DB compared to all other conditions, but differences were unlikely to exceed 5%. The electromagnetic device tended to produce greater amplitudes in the anterior deltoid, while DB tended to produce greater amplitudes in the brachioradialis; amplitude for the biceps brachii was relatively similar between conditions. Overall, any observed differences were relatively modest, equating to magnitudes of ~ 5% and not likely greater than 10%. These differences would seem to be of minimal practical significance., (© 2023. The Author(s).)

Objective: To quantify and describe effect size distributions from exercise therapies across a range of tendinopathies and outcome domains to inform future research and clinical practice through conducting a systematic review with meta-analysis., Design: Systematic review with meta-analysis exploring moderating effects and context-specific small, medium and large thresholds., Eligibility Criteria: Randomised and quasi-randomised controlled trials involving any persons with a diagnosis of rotator cuff, lateral elbow, patellar, Achilles or gluteal tendinopathy of any severity or duration., Methods: Common databases, six trial registries and six grey literature databases were searched on 18 January 2021 (PROSPERO: CRD42020168187). Standardised mean difference (SMD pre ) effect sizes were used with Bayesian hierarchical meta-analysis models to calculate the 0.25 (small), 0.5 (medium) and 0.75 quantiles (large) and compare pooled means across potential moderators. Risk of bias was assessed with Cochrane's Risk of Bias tool., Results: Data were obtained from 114 studies comprising 171 treatment arms 4104 participants. SMD pre effect sizes were similar across tendinopathies but varied across outcome domains. Greater threshold values were obtained for self-reported measures of pain (small=0.5, medium=0.9 and large=1.4), disability (small=0.6, medium=1.0 and large=1.5) and function (small=0.6, medium=1.1 and large=1.8) and lower threshold values obtained for quality of life (small=-0.2, medium=0.3 and large=0.7) and objective measures of physical function (small=0.2, medium=0.4 and large=0.7). Potential moderating effects of assessment duration, exercise supervision and symptom duration were also identified, with greater pooled mean effect sizes estimated for longer assessment durations, supervised therapies and studies comprising patients with shorter symptom durations., Conclusion: The effect size of exercise on tendinopathy is dependent on the type of outcome measure assessed. Threshold values presented here can be used to guide interpretation and assist with further research better establishing minimal important change., Competing Interests: Competing interests: None declared., (© Author(s) (or their employer(s)) 2023. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Abstract: Hall, AJ, Aspe, RR, Craig, TP, Kavaliauskas, M, Babraj, J, and Swinton, PA. The effects of sprint interval training on physical performance: a systematic review and meta-analysis. J Strength Cond Res 37(2): 457-481, 2023-The present study aimed to synthesize findings from published research and through meta-analysis quantify the effect of sprint interval training (SIT) and potential moderators on physical performance outcomes (categorized as aerobic, anaerobic, mixed aerobic-anaerobic, or muscular force) with healthy adults, in addition to assessing the methodological quality of included studies and the existence of small study effects. Fifty-five studies were included (50% moderate methodological quality, 42% low methodological quality), with 58% comprising an intervention duration of ≤4 weeks and an array of different training protocols. Bayesian's meta-analysis of standardized mean differences (SMD) identified a medium effect of improved physical performance with SIT (ES 0.5 = 0.52; 95% credible intervals [CrI]: 0.42-0.62). Moderator analyses identified overlap between outcome types with the largest effects estimated for anaerobic outcomes (ES 0.5 = 0.61; 95% CrI: 0.48-0.75). Moderator effects were identified for intervention duration, sprint length, and number of sprints performed per session, with larger effects obtained for greater values of each moderator. A substantive number of very large effect sizes (41 SMDs > 2) were identified with additional evidence of extensive small study effects. This meta-analysis demonstrates that short-term SIT interventions are effective for developing moderate improvements in physical performance outcomes. However, extensive small study effects, likely influenced by researchers analyzing many outcomes, suggest potential overestimation of reported effects. Future research should analyze fewer a priori selected outcomes and investigate models to progress SIT interventions for longer-term performance improvements., (Copyright © 2022 National Strength and Conditioning Association.)

Background: Circulating biomarkers are often used to investigate the bone response to an acute bout of exercise, but heterogeneity in factors such as study design, quality, selected biomarkers, and exercise and participant characteristics render it difficult to synthesize and evaluate available evidence., Objective: The aim of this study was to quantify the effects of an acute exercise bout on bone biomarkers, along with the influence of potential moderators such as participant, exercise, and design characteristics, using a systematic review and meta-analytic approach., Methods: The protocol was designed in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses Protocols (PRISMA-P) guidelines and prospectively published. Seven databases were systematically searched in accordance with predefined eligibility criteria. Bayesian three-level hierarchical meta-analysis models were used to explore the main effects of acute exercise on bone biomarkers, as well as potential moderating factors. Modelled effect sizes were interpreted according to three metrics, namely (1) evidence of an effect (defined by whether, or how much of, the credible interval [CrI] included zero); (b) the size of that effect (threshold values of 0.01, 0.2, 0.5 and 0.8 were used to describe effect sizes as very small, small, medium and large, respectively); and (c) the level of certainty in the estimated effect (defined using the GRADE framework)., Results: Pooling of outcomes across all designs and categories indicated that an acute bout of exercise increased bone resorption (ES 0.5  0.10, 95% CrI 0.00-0.20) and formation (ES 0.5 0.05, 95% CrI 0.01-0.08) markers but the effects were very small and highly variable. Furthermore, moderator analyses revealed the source of some of this variability and indicated that exercise type and impact loading influenced the bone resorptive response. A moderate increase in C-terminal telopeptide of type 1 collagen (CTX-1) was observed in response to cycling (ES 0.5 0.65, 95% CrI 0.20-0.99), with greater durations and more work leading to larger CTX-1 increases. CTX-1 response peaked within 15 min and 2 h after the exercise bout. Other exercise types did not influence CTX-1. Changes to all bone formation markers were very small and transient, with the very small increases returning to baseline within 15 min of exercise cessation. No major trends for bone formation markers were identified across any of the moderating categories investigated. Certainty of evidence in most outcomes was deemed to be low or very low., Conclusion: The large influence of an acute bout of prolonged cycling on the bone resorption marker CTX-1, alongside the lack of a response of any biomarker to resistance or high-impact exercise types, indicate that these biomarkers may be more useful at investigating potentially osteolytic aspects of exercise, and raises questions about their suitability to investigate the osteogenic potential of different exercise types, at least in the short term and in response to a single exercise bout. Certainty in all outcomes was low or very low, due to factors including risk of bias, lack of non-exercise controls, inconsistency, imprecision and small-study effects., Protocol Registration and Publication: This investigation was prospectively registered on the Open Science Framework Registry ( https://osf.io/6f8dz ) and the full protocol underwent peer review prior to conducting the investigation., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Although many studies have assumed variability reflects variance caused by exercise training, few studies have examined whether interindividual differences in trainability are present following exercise training. The present individual participant data (IPD) meta-analysis sought to: (1) investigate the presence of interindividual differences in trainability for cardiorespiratory fitness (CRF), waist circumference, and body mass; and (2) examine the influence of exercise training and potential moderators on the probability that an individual will experience clinically important differences. The IPD meta-analysis combined data from 1879 participants from eight previously published randomized controlled trials. We implemented a Bayesian framework to: (1) test the hypothesis of interindividual differences in trainability by comparing variability in change scores between exercise and control using Bayes factors; and (2) compare posterior predictions of control and exercise across a range of moderators (baseline body mass index (BMI) and exercise duration, intensity, amount, mode, and adherence) to estimate the proportions of participants expected to exceed minimum clinically important differences (MCIDs) for all three outcomes. Bayes factors demonstrated a lack of evidence supporting a high degree of variance attributable to interindividual differences in trainability across all three outcomes. These findings indicate that interindividual variability in observed changes are likely due to measurement error and external behavioural factors, not interindividual differences in trainability. Additionally, we found that a larger proportion of exercise participants were expected to exceed MCIDs compared with controls for all three outcomes. Moderator analyses identified that larger proportions were associated with a range of factors consistent with standard exercise theory and were driven by mean changes. Practitioners should prescribe exercise interventions known to elicit large mean changes to increase the probability that individuals will experience beneficial changes in CRF, waist circumference and body mass., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The magnitude of change following strength and conditioning (S&C) training can be evaluated comparing effect sizes to thresholds. This study conducted a series of meta-analyses and compiled results to identify thresholds specific to S&C, and create prior distributions for Bayesian updating. Pre- and post-training data from S&C interventions were translated into standardised mean difference (SMD pre ) and percentage improvement (%Improve) effect sizes. Bayesian hierarchical meta-analysis models were conducted to compare effect sizes, develop prior distributions, and estimate 0.25-, 0.5-, and 0.75-quantiles to determine small, medium, and large thresholds, respectively. Data from 643 studies comprising 6574 effect sizes were included in the analyses. Large differences in distributions for both SMD pre and %Improve were identified across outcome domains (strength, power, jump and sprint performance), with analyses of the tails of the distributions indicating potential large overestimations of SMD pre values. Future evaluations of S&C training will be improved using Bayesian approaches featuring the information and priors developed in this study. To facilitate an uptake of Bayesian methods within S&C, an easily accessible tool employing intuitive Bayesian updating was created. It is recommended that the tool and specific thresholds be used instead of isolated effect size calculations and Cohen's generic values when evaluating S&C training.

Studies have suggested a potential role of endothelial dysfunction and atherosclerosis in the pathophysiology of COVID-19. Herein, we tested whether brachial flow-mediated dilation (FMD) and carotid intima-media thickness (cIMT) measured upon hospital admission are associated with acute in-hospital outcomes in patients hospitalized with COVID-19. A total of 211 patients hospitalized with COVID-19 were submitted to assessments of FMD and mean and maximum cIMT (cIMT mean and cIMT max ) within the first 72 h of hospital admission. Study primary outcome was a composite of intensive care unit admission, mechanical ventilation, or death during the hospitalization. These outcomes were also considered independently. Thrombotic events were included as a secondary outcome. Odds ratios (ORs) and confidence intervals (CIs) were calculated using unadjusted and adjusted multivariable logistic regression models. Eighty-eight (42%) participants demonstrated at least one of the composite outcomes. cIMT mean and cIMT max were predictors of mortality and thrombotic events in the univariate analysis (cIMT mean and mortality: unadjusted OR 12.71 [95% CI 1.71-94.48]; P = 0.014; cIMT mean and thrombotic events: unadjusted OR 11.94 [95% CI 1.64-86.79]; P = 0.015; cIMT max and mortality: unadjusted OR 8.47 [95% CI 1.41-51.05]; P = 0.021; cIMT max and thrombotic events: unadjusted OR 12.19 [95% CI 2.03-73.09]; P = 0.007). However, these associations were no longer present after adjustment for potential confounders ( P > 0.05). In addition, FMD% was not associated with any outcome. In conclusion, cIMT and FMD are not independent predictors of clinical outcomes in patients hospitalized with COVID-19. These results suggest that subclinical atherosclerosis and endothelial dysfunction may not be the main drivers of COVID-19 complications in patients hospitalized with COVID-19. NEW & NOTEWORTHY Studies have suggested a role of endothelial dysfunction and atherosclerosis in COVID-19 pathophysiology. In this prospective cohort study, we assessed the prognostic value of carotid intima-media thickness (IMT) and flow-mediated dilation (FMD) in patients with COVID-19. Carotid IMT and FMD were not independent predictors of major outcomes. These results suggest that other risk factors may be the main drivers of clinical outcomes in patients with COVID-19.

ABSTRACT Sodium bicarbonate (SB) is considered an effective ergogenic supplement for improving high-intensity exercise capacity and performance, although recent data suggests that women may be less amenable to its ergogenic effects than men. Currently, an apparent paucity of data on women means no consensus exists on whether women benefit from SB supplementation. The aim of the current study was to quantify the proportion of the published literature on SB supplementation that includes women, and to synthesise the evidence regarding its effects on blood bicarbonate and exercise performance in women by performing a systematic review and meta-analysis. Electronic searches of the literature were undertaken using three databases (MEDLINE, Embase, SPORTDiscus) to identify relevant articles. All meta-analyses were performed within a Bayesian framework. A total of 149 SB articles were identified, 11 of which contained individual group data for women. Results indicated a pooled blood bicarbonate increase of 7.4 [95%CrI: 4.2-10.4 mmol·L -1 ] following supplementation and a pooled standardised exercise effect size of 0.37 [95%CrI: -0.06-0.92]. The SB literature is skewed, with only 20% (30 studies) of studies employing female participants, of which only 11 studies (7.4%) provided group analyses exclusively in women. Despite the small amount of available data, results are consistent in showing that SB supplementation in women leads to large changes in blood bicarbonate and that there is strong evidence for a positive ergogenic effect on exercise performance that is likely to be small to medium in magnitude.HighlightsThis study aimed to quantify the proportion of the published literature on sodium bicarbonate supplementation that includes women and to synthesise the evidence regarding its ergogenic effect on women, using a systematic review and meta-analytic approach.The sodium bicarbonate literature is skewed, with only 30 studies (20%) employing female participants, of which only 11 studies (7.4%) provided group analyses exclusively in women.Despite the small amount of available data, results are consistent in showing that sodium bicarbonate supplementation in women leads to large changes in blood bicarbonate and that there is strong evidence for a positive ergogenic effect on exercise performance that is likely small to medium in magnitude.Based on these findings, we do not believe there is any evidence to support sex-specific sodium bicarbonate dosing recommendations and that current recommendations of 0.2-0.3 g·kg -1 BM of SB taken 60-180 min prior to high-intensity exercise appear appropriate for the female athlete.

Background: Extracellular buffering supplements [sodium bicarbonate (SB), sodium citrate (SC), sodium/calcium lactate (SL/CL)] are ergogenic supplements, although questions remain about factors which may modify their effect., Objective: To quantify the main effect of extracellular buffering agents on exercise outcomes, and to investigate the influence of potential moderators on this effect using a systematic review and meta-analytic approach., Methods: This study was designed in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Three databases were searched for articles that were screened according to inclusion/exclusion criteria. Bayesian hierarchical meta-analysis and meta-regression models were used to investigate pooled effects of supplementation and moderating effects of a range of factors on exercise and biomarker responses., Results: 189 articles with 2019 participants were included, 158 involving SB supplementation, 30 with SC, and seven with CL/SL; four studies provided a combination of buffering supplements together. Supplementation led to a mean estimated increase in blood bicarbonate of + 5.2 mmol L -1 (95% credible interval (CrI) 4.7-5.7). The meta-analysis models identified a positive overall effect of supplementation on exercise capacity and performance compared to placebo [ES 0.5  = 0.17 (95% CrI 0.12-0.21)] with potential moderating effects of exercise type and duration, training status and when the exercise test was performed following prior exercise. The greatest ergogenic effects were shown for exercise durations of 0.5-10 min [ES 0.5  = 0.18 (0.13-0.24)] and > 10 min [ES 0.5  = 0.22 (0.10-0.33)]. Evidence of greater effects on exercise were obtained when blood bicarbonate increases were medium (4-6 mmol L -1 ) and large (> 6 mmol L -1 ) compared with small (≤ 4 mmol L -1 ) [β Small:Medium  = 0.16 (95% CrI 0.02-0.32), β Small:Large  = 0.13 (95% CrI - 0.03 to 0.29)]. SB (192 outcomes) was more effective for performance compared to SC (39 outcomes) [β SC:SB  = 0.10 (95% CrI - 0.02 to 0.22)]., Conclusions: Extracellular buffering supplements generate large increases in blood bicarbonate concentration leading to positive overall effects on exercise, with sodium bicarbonate being most effective. Evidence for several group-level moderating factors were identified. These data can guide an athlete's decision as to whether supplementation with buffering agents might be beneficial for their specific aims., (© 2021. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

The purpose of this research was to assess relationships between subjective and external measures of training load in professional youth footballers, whilst accounting for the effect of the stage of the season. Data for ratings of perceived exertion (RPE) and seven global positioning systems (GPS) derived measures were collected from 20 players (age = 17.4 ± 1.3 yrs, height = 178.0 ± 8.1 cm, mass = 71.8 ± 7.2 kg) across a 47-week season. The season was categorised by a pre-season phase, and two competitive phases (Comp1, Comp2). The structure of the data were investigated using principal component analysis. An extraction criterion of component with eigenvalues ≥1.0 was used. Two components were retained for the pre-season period explaining a cumulative variance of 77.1%. Single components were retained for both Comp1 and Comp2 explaining 73.3% and 74.3% of variance, respectively. Identification of single components may suggest that measures are related and can be used interchangeably, however these interpretations should be considered with caution. The identification of multiple components in the pre-season phase suggests that univariate measures may not be sufficient when considering load experienced. These results suggest that factoring load based on measures of volume and intensity should be considered.

There is growing evidence that supplementation with carnosine, or its rate-limiting precursor β-alanine, can ameliorate aspects of metabolic dysregulation that occur in diabetes and its related conditions. The purpose of this systematic review and meta-analysis was to evaluate the effect of carnosine or β-alanine supplementation on markers of glycemic control and insulin resistance in humans and animals. We performed a systematic search of 6 electronic databases up to 31 December 2020. Primary outcomes were changes in 1) fasting glucose, 2) glycated hemoglobin (HbA1c), and 3) 2-h glucose following a glucose-tolerance test. A set of additional outcomes included fasting insulin and homeostatic model assessment of β-cell function (HOMA-β) and insulin resistance (HOMA-IR). We assessed risk of bias using the Cochrane risk of bias (RoB) 2.0 (human studies) and the Systematic Review Center for Laboratory Animal Experimentation (SYRCLE) RoB (animal studies) tools; and used the Grading of Recommendations Assessment, Development, and Evaluation (GRADE) approach to assess certainty. We used Bayesian hierarchical random-effects models, with informative priors for human data and noninformative priors for animal data. Inferences were made on posterior samples generated by Hamiltonian Markov Chain Monte Carlo using 90% credible intervals (90% CrI) and calculated probabilities. Twenty studies (n = 4 human, n = 16 rodent) were included, providing data for 2 primary outcomes (fasting glucose and HbA1c) and 3 additional outcomes (fasting insulin, HOMA-β, and HOMA-IR). The model provides evidence that supplementation decreases fasting glucose [humans: mean difference (MD)0.5 = -0.95 mmol · L-1 (90% CrI: -2.1, 0.08); rodent: MD0.5 = -2.26 mmol · L-1 (90% CrI: -4.03, -0.44)], HbA1c [humans: MD0.5 = -0.91% (90% CrI: -1.46, -0.39); rodents: MD0.5 = -1.05% (90% CrI: -1.64, -0.52)], HOMA-IR [humans: standardized mean difference (SMD)0.5 = -0.41 (90% CrI: -0.82, -0.07); rodents: SMD0.5 = -0.63 (90% CrI: -1.98, 0.65)], and fasting insulin [humans: SMD0.5 = -0.41 (90% CrI: -0.77, -0.07)]. GRADE assessment showed our certainty in the effect estimate of each outcome to be moderate (human outcomes) or very low (rodent outcomes). Supplementation with carnosine or β-alanine may reduce fasting glucose, HbA1c, and HOMA-IR in humans and rodents, and fasting insulin in humans; both compounds show potential as therapeutics to improve glycemic control and insulin resistance. This review was registered at PROSPERO as CRD42020191588., (© The Author(s) 2021. Published by Oxford University Press on behalf of the American Society for Nutrition.)

Exercising women report three to six times more ACL tears than men, which happen, in the majority of cases, with a non-contact mechanism. This sex disparity has, in part, been attributed to the differences in reproductive hormone profiles between men and women. Many studies have shown that anterior knee (AK) laxity and the rate of non-contact ACL injuries vary across the menstrual cycle, but these data are inconsistent. Similarly, several studies have investigated the potential protective effect of hormonal contraceptives on non-contact ACL injuries, but their conclusions are also variable. The purpose of this systematic review and meta-analysis is to, identify, evaluate and summarise the effects of endogenous and exogenous ovarian hormones on AK laxity (primary outcome) and the occurrence of non-contact ACL injuries (secondary outcome) in women. We will perform a systematic search for all observational studies conducted on this topic. Studies will be retrieved by searching electronic databases, clinical trial registers, author's personal files and cross-referencing selected studies. Risk of bias will be assessed using the Newcastle Ottawa Quality Assessment Scale for Cohort and Case-Control Studies. Certainty in the cumulative evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation approach. The meta-analyses will use a Bayesian approach to address specific research questions in a more intuitive and probabilistic manner. This review is registered on the international database of prospectively registered systematic reviews (PROSPERO; CRD42021252365)., Competing Interests: Competing interests: EN, EF, SJS, PAS, ED, KE, JP, JJM, and CS declare that they have no competing interests. KES is the recipient of a GnRB arthrometer from Bergstrom Nutrition., (© Author(s) (or their employer(s)) 2021. Re-use permitted under CC BY-NC. No commercial re-use. See rights and permissions. Published by BMJ.)

Higher daily protein intake, with an emphasis on leucine content, is thought to mitigate age-related anabolic resistance, potentially counteracting age-related morphological and functional declines. The present study investigated potential associations between total daily leucine intake and dependent variables, including quadriceps muscle cross-sectional area (CSA) and maximum dynamic muscle strength (1-RM) in a cohort of healthy free-living older individuals of both sexes ( n = 67; 34/33 men/women). Participants performed three 24 h dietary recalls and underwent a magnetic resonance imaging exam followed by 1-RM tests. Our results demonstrate moderate associations between total daily leucine and both quadriceps CSA ( r = 0.42; p = 0.004) and 1-RM ( r = 0.45; p = 0.001). Furthermore, our exploratory biphasic linear regression analyses, adjusted for sex, age, and protein intake relative to body weight, revealed a plateau for daily leucine intake and muscle mass and muscle strength (~7.6-8.0 g·day -1 ) in older adults. In conclusion, we demonstrated that total daily leucine intake is associated with muscle mass and strength in healthy older individuals and this association remains after controlling for multiple factors, including overall protein intake. Furthermore, our breakpoint analysis revealed non-linearities and a potential threshold for habitual leucine intake, which may help guide future research on the effects of chronic leucine intake in age-related muscle loss.

Purpose: To quantify and describe relationships between subjective and external measures of training load in professional youth soccer players., Methods: Data from differential ratings of perceived exertion (dRPE) and 7 measures of external training load were collected from 20 professional youth soccer players over a 46-week season. Relationships were described by repeated-measures correlation, principal component analysis, and factor analysis with oblimin rotation., Results: Significant positive (.44 ≤ r ≤ .99; P < .001) within-individual correlations were obtained across dRPE and all external training load measures. Correlation magnitudes were found to decrease when training load variables were expressed per minute. Principal component analysis provided 2 components, which described 83.3% of variance. The first component, which described 72.9% of variance, was heavily loaded by all measures of training load, while the second component, which described 10.4% of the variance, appeared to have a split between objective and subjective measures of volume and intensity. Exploratory factor analysis identified 4 theoretical factors, with correlations between factors ranging from .5 to .8. These factors could be theoretically described as objective volume, subjective volume, objective running, and objective high-intensity measures. Removing dRPE measures from the analysis altered the structure of the model, providing a 3-factor solution., Conclusions: The dRPE measures are significantly correlated with a range of external training load measures and with each other. More in-depth analysis showed that dRPE measures were highly related to each other, suggesting that, in this population, they would provide practitioners with similar information. Further analysis provided characteristic groupings of variables.

Health coaching has emerged as a potential supporting tool for health professionals to overcome behavioral barriers, but its efficacy in weight management remains unclear. We conducted a systematic review and meta-analysis to synthesize and evaluate the quality of evidence supporting the use of self-reported health coaching for weight loss. Seven electronic databases (PubMed, Web of Science, Scopus, Cochrane, Psyinfo, Virtual Health Library, and Scielo) were independently searched from inception to May 2020. This review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines and quality of evidence was assessed using the Grading of Recommendations, Assessment, Development and Evaluation recommendations. Any study that investigated a self-reported health coaching intervention with the goal of inducing weight loss in individuals of any age, health, or training status was considered for inclusion. Quantitative data were analyzed using multilevel hierarchical metaregression models conducted within a Bayesian framework. A total of 653 studies were screened and 38 were selected for inclusion. The quality of evidence supporting outcomes based on the entire evidence base was very low and studies were deemed to have high risk of bias. Meta-analysis of controlled studies provided evidence of an effect favoring coaching compared with usual care but was trivial in magnitude [effect size (ES)0.5: -0.09; 95% credible interval (CrI): -0.17, -0.02]. The multilevel extension of Egger's regression-intercept test indicated the existence of publication bias, whereas a sensitivity analysis based only on those studies deemed to be of high quality provided no evidence of an effect of coaching on weight loss (ES0.5: -0.04; 95% CrI: -0.12, 0.09). Considered collectively, the results of this investigation indicate that the available evidence is not of sufficient quality to support the use of self-reported health coaching as a health care intervention for weight loss. This trial was registered at Prospective Register of Systematic Reviews (PROSPERO) as CRD42020159023., (© The Author(s) 2020. Published by Oxford University Press on behalf of the American Society for Nutrition.)

High training demands throughout the competitive season in female collegiate soccer players have been shown to induce changes in biomarkers indicative of stress, inflammation, and reproduction, which may be exacerbated in athletes using oral contraceptives (OCs). This study aimed to compare biomarkers and body composition between OC-using and nonusing (CON) female soccer players throughout a competitive season. Female collegiate soccer players were stratified into two groups based on their reported OC use at the start of preseason (OC: n = 6; CON: n = 17). Before the start of preseason and immediately postseason, athletes underwent a battery of performance tests. Blood draws and body composition assessments were performed before preseason, on wks 2 , 4 , 8 , and 12 of the season, and postseason. Area-under-the-curve ratios (OC AUC :CON AUC ) indicated the OC group were exposed to substantially higher levels of sex hormone-binding globulin (AUC ratio  = 1.4, probability =  P > 0.999), total cortisol (1.7; P > 0.999), C-reactive protein (5.2; P > 0.999), leptin (1.4; P = 0.990), growth hormone (1.5; P = 0.97), but substantively lower amounts of estradiol (0.36; P < 0.001), progesterone (0.48; P = 0.008), free testosterone (0.58; P < 0.001), follicle-stimulating hormone (0.67; P < 0.001), and creatine kinase (0.33, P < 0.001) compared with the CON across the season. Both groups increased fat free mass over the season, but CON experienced a greater magnitude of increase along with decreased body fat percentage. Although similar training loads were observed between groups over the season, the elevated exposure to stress, inflammatory, and metabolic biomarkers over the competitive season in OC users may have implications on body composition, training adaptations, and recovery in female athletes. NEW & NOTEWORTHY This study highlights the influence of OC use on physiological changes that occur over a 4-mo intense, competitive season and the differential systemic exposure to biomarkers, specifically those of inflammation, stress, anabolism, and energy balance, between OC-using and nonusing soccer players. Additionally, this study provides insight into changes in body composition with prolonged training between female athletes with and without OC use.

Objective: The objective of this review is to synthesize the best available evidence on the effectiveness of interventions that have used a combination of extracorporeal shockwave therapy and plantar fascia-specific stretching to treat plantar heel pain compared to any other non-surgical intervention., Introduction: Recent evidence suggests combining shockwave therapy and plantar fascia stretching may be more effective than other treatments for plantar heel pain. However, no systematic reviews have been conducted on the topic and optimal treatment protocols and clinical recommendations are lacking., Inclusion Criteria: Randomized controlled trials assessing the effectiveness of combined shockwave therapy and plantar stretching for plantar heel pain in adults will be included., Methods: The authors will search a wide range of sources to identify both published and unpublished studies via EBSCOhost, including, but not limited to MEDLINE, SPORTDiscus, CINAHL, Cochrane Central Register of Controlled Trials (CENTRAL), and Allied and Complementary Medicine Database (AMED). Studies published in a language other than English will only be considered if a translation is available. The JBI systematic review methodology will be followed when conducting the review. Data synthesis will be conducted using meta-analysis or narrative synthesis, where appropriate., Systematic Review Registration Number: PROSPERO CRD42020171538., Competing Interests: The authors declare no conflict of interest., (Copyright © 2021 JBI.)

Background: Diabetes is a major public health issue and there is a need to develop low-cost, novel interventions to prevent or reduce disease progression. Growing evidence shows that supplementation with carnosine, or its rate-limiting precursor β-alanine, can ameliorate aspects of the metabolic dysregulation that occurs in diabetes. There is, however, a need to develop a better understanding of the magnitude of effect and the factors associated with positive outcomes. The purpose of this systematic review and meta-analysis is to evaluate the effect of carnosine or β-alanine supplementation on markers of glycaemic control and insulin resistance in humans and animals., Methods: We will perform a systematic search for randomised and non-randomised controlled trials. Studies will be retrieved by searching electronic databases, clinical trial registers, author review, and cross-referencing. Primary outcomes include changes in (i) fasting glucose, (ii) glycated haemoglobin, and (iii) 2-h glucose following a glucose tolerance test. A set of additional outcomes includes other markers of glycaemic control and insulin resistance. Risk of bias (RoB) will be assessed using the Cochrane RoB 2.0 tool (human studies) and the Systematic Review Centre for Laboratory Animal Experimentation (SYRCLE) RoB tool (animal studies). Confidence in the cumulative evidence will be assessed using the Grading of Recommendations Assessment, Development and Evaluation (GRADE) approach. All meta-analyses will be conducted within a Bayesian framework, providing a flexible modelling approach to account for uncertainty in model parameters and underlying structures within the data., Discussion: By including all available human and animal data, we will provide the most comprehensive overview on the topic to date. The results will have implications for those working in prediabetes, diabetes, and metabolic health in general and may lead to the development of new treatment approaches., Dissemination: Study results will be presented at a professional conference and published in a peer-reviewed journal., Systematic Review Registration: CRD42020191588.

Background: Mental health difficulties are highly prevalent, yet access to support is limited by barriers of stigma, cost, and availability. These issues are even more prevalent in low- and middle-income countries, and digital technology is one potential way to overcome these barriers. Digital mental health interventions are effective but often struggle with low engagement rates, particularly in the absence of human support. Chatbots could offer a scalable solution, simulating human support at a lower cost. Objective: To complete a preliminary evaluation of engagement and effectiveness of Vitalk, a mental health chatbot, at reducing anxiety, depression and stress. Methods: Real world data was analyzed from 3,629 Vitalk users who had completed the first phase of a Vitalk program ("less anxiety," "less stress" or "better mood"). Programs were delivered through written conversation with a chatbot. Engagement was calculated from the number of responses sent to the chatbot divided by days in the program. Results: Users sent an average of 8.17 responses per day. For all three programs, target outcome scores reduced between baseline and follow up with large effect sizes for anxiety (Cohen's d = -0.85), depression (Cohen's d = -0.91) and stress (Cohen's d = -0.81). Increased engagement resulted in improved post-intervention values for anxiety and depression. Conclusion: This study highlights a chatbot's potential to reduce mental health symptoms in the general population within Brazil. While findings show promise, further research is required., Competing Interests: IH, KD, and MK are employees of TNH Health. TNH Health created the chatbot and paid for the cost of submitting the publication. The remaining authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2020 Daley, Hungerbuehler, Cavanagh, Claro, Swinton and Kapps.)

Autoregulation is a process that is used to manipulate training based primarily on the measurement of an individual's performance or their perceived capability to perform. Despite being established as a training framework since the 1940s, there has been limited systematic research investigating its broad utility. Instead, researchers have focused on disparate practices that can be considered specific examples of the broader autoregulation training framework. A primary limitation of previous research includes inconsistent use of key terminology (e.g., adaptation, readiness, fatigue, and response) and associated ambiguity of how to implement different autoregulation strategies. Crucially, this ambiguity in terminology and failure to provide a holistic overview of autoregulation limits the synthesis of existing research findings and their dissemination to practitioners working in both performance and health contexts. Therefore, the purpose of the current review was threefold: first, we provide a broad overview of various autoregulation strategies and their development in both research and practice whilst highlighting the inconsistencies in definitions and terminology that currently exist. Second, we present an overarching conceptual framework that can be used to generate operational definitions and contextualise autoregulation within broader training theory. Finally, we show how previous definitions of autoregulation fit within the proposed framework and provide specific examples of how common practices may be viewed, highlighting their individual subtleties.

Background: Concentrations of endogenous sex hormones fluctuate across the menstrual cycle (MC), which could have implications for exercise performance in women. At present, data are conflicting, with no consensus on whether exercise performance is affected by MC phase., Objective: To determine the effects of the MC on exercise performance and provide evidence-based, practical, performance recommendations to eumenorrheic women., Methods: This review followed the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Four databases were searched for published experimental studies that investigated the effects of the MC on exercise performance, which included at least one outcome measure taken in two or more defined MC phases. All data were meta-analysed using multilevel models grounded in Bayesian principles. The initial meta-analysis pooled pairwise effect sizes comparing exercise performance during the early follicular phase with all other phases (late follicular, ovulation, early luteal, mid-luteal and late luteal) amalgamated. A more comprehensive analysis was then conducted, comparing exercise performance between all phases with direct and indirect pairwise effect sizes through a network meta-analysis. Results from the network meta-analysis were summarised by calculating the Surface Under the Cumulative Ranking curve (SUCRA). Study quality was assessed using a modified Downs and Black checklist and a strategy based on the recommendations of the Grading of Recommendations Assessment Development and Evaluation (GRADE) working group., Results: Of the 78 included studies, data from 51 studies were eligible for inclusion in the initial pairwise meta-analysis. The three-level hierarchical model indicated a trivial effect for both endurance- and strength-based outcomes, with reduced exercise performance observed in the early follicular phase of the MC, based on the median pooled effect size (ES 0.5  = - 0.06 [95% credible interval (CrI): - 0.16 to 0.04]). Seventy-three studies had enough data to be included in the network meta-analysis. The largest effect was identified between the early follicular and the late follicular phases of the MC (ES 0.5  = - 0.14 [95% CrI: - 0.26 to - 0.03]). The lowest SUCRA value, which represents the likelihood that exercise performance is poor, or among the poorest, relative to other MC phases, was obtained for the early follicular phase (30%), with values for all other phases ranging between 53 and 55%. The quality of evidence for this review was classified as "low" (42%)., Conclusion: The results from this systematic review and meta-analysis indicate that exercise performance might be trivially reduced during the early follicular phase of the MC, compared to all other phases. Due to the trivial effect size, the large between-study variation and the number of poor-quality studies included in this review, general guidelines on exercise performance across the MC cannot be formed; rather, it is recommended that a personalised approach should be taken based on each individual's response to exercise performance across the MC.

Background: Oral contraceptive pills (OCPs) are double agents, which downregulate endogenous concentrations of oestradiol and progesterone whilst simultaneously providing daily supplementation of exogenous oestrogen and progestin during the OCP-taking days. This altered hormonal milieu differs significantly from that of eumenorrheic women and might impact exercise performance, due to changes in ovarian hormone-mediated physiological processes., Objective: To explore the effects of OCPs on exercise performance in women and to provide evidence-based performance recommendations to users., Methods: This review complied with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. A between-group analysis was performed, wherein performance of OCP users was compared with naturally menstruating women, and a within-group analysis was conducted, wherein performance during OCP consumption was compared with OCP withdrawal. For the between-group analysis, women were phase matched in two ways: (1) OCP withdrawal versus the early follicular phase of the menstrual cycle and (2) OCP consumption versus all phases of the menstrual cycle except for the early follicular phase. Study quality was assessed using a modified Downs and Black Checklist and a strategy based on the recommendations of the Grading of Recommendations Assessment Development and Evaluation working group. All meta-analyses were conducted within a Bayesian framework to facilitate probabilistic interpretations., Results: 42 studies and 590 participants were included. Most studies (83%) were graded as moderate, low or very low quality, with 17% achieving high quality. For the between-group meta-analysis comparing OCP users with naturally menstruating women, posterior estimates of the pooled effect were used to calculate the probability of at least a small effect (d ≥ 0.2). Across the two between-group comparison methods, the probability of a small effect on performance favouring habitual OCP users was effectually zero (p < 0.001). In contrast, the probability of a small effect on performance favouring naturally menstruating women was moderate under comparison method (1) (d ≥ 0.2; p = 0.40) and small under comparison method (2) (d ≥ 0.2; p = 0.19). Relatively large between-study variance was identified for both between-group comparisons ([Formula: see text] 0.5  = 0.16 [95% credible interval (CrI) 0.01-0.44] and [Formula: see text] 0.5  = 0.22 [95% CrI 0.06-0.45]). For the within-group analysis comparing OCP consumption with withdrawal, posterior estimates of the pooled effect size identified almost zero probability of a small effect on performance in either direction (d ≥ 0.2; p ≤ 0.001)., Conclusions: OCP use might result in slightly inferior exercise performance on average when compared to naturally menstruating women, although any group-level effect is most likely to be trivial. Practically, as effects tended to be trivial and variable across studies, the current evidence does not warrant general guidance on OCP use compared with non-use. Therefore, when exercise performance is a priority, an individualised approach might be more appropriate. The analysis also indicated that exercise performance was consistent across the OCP cycle.

Competing Interests: Competing interests: BS has previously received financial support from Natural Alternatives International (NAI), a company that produces β-alanine, to undertake a study unrelated to this review. NAI have also provided β-alanine supplements free of charge for further experimental investigations and supported open access page charges for several of the author’s manuscripts. NAI have not had any input (financial, intellectual or otherwise) into this review.

β-Alanine supplementation is one of the world's most commonly used sports supplements, and its use as a nutritional strategy in other populations is ever-increasing, due to evidence of pleiotropic ergogenic and therapeutic benefits. Despite its widespread use, there is only limited understanding of potential adverse effects. To address this, a systematic risk assessment and meta-analysis was undertaken. Four databases were searched using keywords and Medical Subject Headings. All human and animal studies that investigated an isolated, oral, β-alanine supplementation strategy were included. Data were extracted according to 5 main outcomes, including 1) side effects reported during longitudinal trials, 2) side effects reported during acute trials, 3) effect of supplementation on circulating health-related biomarkers, 4) effect of supplementation on skeletal muscle taurine and histidine concentration, and 5) outcomes from animal trials. Quality of evidence for outcomes was ascertained using the Grading of Recommendations Assessment Development and Evaluation (GRADE) framework, and all quantitative data were meta-analyzed using multilevel models grounded in Bayesian principles. In total, 101 human and 50 animal studies were included. Paraesthesia was the only reported side effect and had an estimated OR of 8.9 [95% credible interval (CrI): 2.2, 32.6] with supplementation relative to placebo. Participants in active treatment groups experienced similar dropout rates to those receiving the placebo treatment. β-Alanine supplementation caused a small increase in circulating alanine aminotransferase concentration (effect size, ES: 0.274, CrI: 0.04, 0.527), although mean data remained well within clinical reference ranges. Meta-analysis of human data showed no main effect of β-alanine supplementation on skeletal muscle taurine (ES: 0.156; 95% CrI: -0.38, 0.72) or histidine (ES: -0.15; 95% CrI: -0.64, 0.33) concentration. A main effect of β-alanine supplementation on taurine concentration was reported for murine models, but only when the daily dose was ≥3% β-alanine in drinking water. The results of this review indicate that β-alanine supplementation within the doses used in the available research designs, does not adversely affect those consuming it., (Copyright © American Society for Nutrition 2019.)

The concept of personalized nutrition and exercise prescription represents a topical and exciting progression for the discipline given the large inter-individual variability that exists in response to virtually all performance and health related interventions. Appropriate interpretation of intervention-based data from an individual or group of individuals requires practitioners and researchers to consider a range of concepts including the confounding influence of measurement error and biological variability. In addition, the means to quantify likely statistical and practical improvements are facilitated by concepts such as confidence intervals (CIs) and smallest worthwhile change (SWC). The purpose of this review is to provide accessible and applicable recommendations for practitioners and researchers that interpret, and report personalized data. To achieve this, the review is structured in three sections that progressively develop a statistical framework. Section 1 explores fundamental concepts related to measurement error and describes how typical error and CIs can be used to express uncertainty in baseline measurements. Section 2 builds upon these concepts and demonstrates how CIs can be combined with the concept of SWC to assess whether meaningful improvements occur post-intervention. Finally, section 3 introduces the concept of biological variability and discusses the subsequent challenges in identifying individual response and non-response to an intervention. Worked numerical examples and interactive Supplementary Material are incorporated to solidify concepts and assist with implementation in practice.

Introduction: Trauma remains the fourth leading cause of death in western countries and is the leading cause of death in the first four decades of life. NICE guidance in 2016 advocated the attendance of pre-hospital critical care trauma team (PHCCT) in the pre-hospital stage of the care of patients with major trauma. Previous publications support dispatch by clinicians who are also actively involved in the delivery of the PHCCT service; however there is a lack of objective outcome measures across the current reviewed evidence base. In this study, we aimed to assess the accuracy of PHCCT clinician led dispatch, when measured by Injury Severity Score (ISS)., Methods: A retrospective cohort study over a 2 year period pre and post implementation of a PHCCT clinician led dispatch of PHCCT for potential major trauma patients, using national ambulance data combined with national trauma registry data., Results: A total of 99,702 trauma related calls were made to SAS including 495 major trauma patients with an ISS >15, and a total of 454 dispatches of a PHCCT. Following the introduction of a PHCCT clinician staffed trauma desk, the sensitivity for major trauma was increased from 11.3% to 25.9%. The difference in sensitivity between the pre and post trauma desk group was significant at 14.6% (95% CI 7.4%-21.4%, p < .001)., Discussion: The results from the study support the results from other studies recommending that a PHCCT clinician should be located in ambulance control to identify major trauma patients as early as possible and co-ordinate the response., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

Objective: To quantify the effects of acute hypoxic exposure on exercise capacity and performance, which includes continuous and intermittent forms of exercise., Design: A systematic review was conducted with a three-level mixed effects meta-regression. The ratio of means method was used to evaluate main effects and moderators providing practical interpretations with percentage change., Data Sources: A systemic search was performed using three databases (Google scholar, PubMed and SPORTDiscus). Eligibility criteria for selecting studies: Inclusion was restricted to investigations that assessed exercise performance (time trials (TTs), sprint and intermittent exercise tests) and capacity (time to exhaustion test, TTE) with acute hypoxic (<24 h) exposure and a normoxic comparator., Results: Eighty-two outcomes from 53 studies (N = 798) were included in this review. The results show an overall reduction in exercise performance/capacity -17.8 ± 3.9% (95% CI -22.8% to -11.0%), which was significantly moderated by -6.5 ± 0.9% per 1000 m altitude elevation (95% CI -8.2% to -4.8%) and oxygen saturation (-2.0 ± 0.4%; 95% CI -2.9% to -1.2%). TT (-16.2 ± 4.3%; 95% CI -22.9% to -9%) and TTE (-44.5 ± 6.9%; 95% CI -51.3% to -36.7%) elicited a negative effect, whilst indicating a quadratic relationship between hypoxic magnitude and both TTE and TT performance. Furthermore, exercise less than 2 min exhibited no ergolytic effect from acute hypoxia. Summary/Conclusion: This review highlights the ergolytic effect of acute hypoxic exposure, which is curvilinear for TTE and TT performance with increasing hypoxic levels, but short duration intermittent and sprint exercise seem to be unaffected.

Context: The scientific literature shows conflicting evidence about the relationship between adiposity and bone mass in overweight and obese populations. The aim of this review was to quantify the correlation between adipose mass (absolute and relative) and bone mineral density (BMD) in overweight and obese populations. Three databases were searched electronically. In addition, reference lists of relevant articles were screened. A total of 16 studies, comprising 2587 participants and 75 correlation coefficients were selected for inclusion in the review. Data were extracted from each study using a standardized form. Multilevel modeling indicated opposing relationships between BMD and adiposity: absolute adiposity correlated positively, and relative adiposity negatively, with BMD. Sex and age were the primary moderators of these relationships. Strong evidence supported a negative relationship between relative adipose mass and BMD in men (R = -0.37; 95%CI, -0.57 to -0.12) and in those aged less than 25 years (R = -0.28; 95%CI, -0.45 to -0.08). To prevent bone loss in overweight and obese populations, nutrition- and exercise-based interventions that focus on a controlled reduction of adipose mass with concomitant preservation of lean mass are recommended. : PROSPERO no. CRD42015024313., (© The Author(s) 2017. Published by Oxford University Press on behalf of the International Life Sciences Institute. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com)